Type 2 Diabetes Prevention

Type 2 diabetes is becoming so prevalent in the United States that some have described it as "approaching epidemic status" (McFarlane et al. 2003). Various studies have shown that the risk of diabetes can be cut in half in the most high-risk individuals in all ethnic groups through interventions such as lifestyle changes (Tuomilehto and Lindström 2003). Yet for many patients, dramatic lifestyle changes are difficult because of social, cultural, psychological, and sometimes economic factors.

Other studies have looked at ways to prevent diabetes through medication. Since type 2 diabetes carries with it high rates of illness and death from cardiovascular disease, prevention would have a major impact on public health (McFarlane et al. 2003). A diabetes prevention program that includes medication would be easier to administer for some than lifestyle changes.

The DREAM Study

The Diabetes Reduction Assessment with Ramipril and Rosiglitazone Medication (DREAM) Study was designed to investigate whether two drugs, ramipril (an ACE inhibitor) and rosiglitazone (a thiazolidinedione drug, or TZD), are effective in preventing type 2 diabetes. The study was centered around a three-year, placebo-controlled trial on over 5000 people with pre-diabetes but no pre-existing cardiovascular disease (Scheen 2006).

The results of the study showed that ramipril did not prevent type 2 diabetes, though it did appear to "cure" pre-diabetes in some patients. A more significant outcome was found for rosiglitazone. For patients on this drug, the incidence of type 2 diabetes was reduced by almost 60%, and over 70% saw their pre-diabetes "cured" (Scheen 2006).

Can Rosiglitazone Prevent Type 2 Diabetes?

The risk reduction of almost 60% with rosiglitazone translates into 144 out of 1000 patients who were prevented from developing type 2 diabetes. (See "Confusing and Misleading Statistics" for more information on interpreting medical statistics.) The cost to treat those 1000 patients over three years would be about $6 million in U.S. dollars ($2000 per patient per year). The DREAM study did not make it clear whether rosiglitazone conferred a lasting preventive effect or whether the risk returned to normal when treatment ceased; follow-up studies are needed. Complicating the question even further is the fact that between 4 and 5 of those 1000 would suffer heart failure as a result of rosiglitazone treatment. (Davidson 2007)

Because of these considerations, the value of rosiglitazone treatment as a part of a diabetes prevention plan is debatable. The drug is expensive and carries a risk of gravely serious side effects. Additionally, it would delay the onset of type 2 diabetes in only about 15% of pre-diabetes patients. Lifestyle changes may be more difficult for patients, but they do not carry these significant negative factors.